Pyrrolidine dithiocarbamate administered during ex-vivo lung perfusion promotes rehabilitation of injured donor rat lungs obtained after prolonged warm ischemia

Les greffons pulmonaires prélevés chez des donneurs décédés après arrêt circulatoire (DCD, donation after circulatory death) subissent une ischémie chaude et sont à haut risque de lésion de reperfusion après une transplantation. Ces greffons pourraient être traités et reconditionnés par voie pharmacologique en utilisant la perfusion ex-vivo de poumon (EVLP, ex-vivo lung perfusion). Étant donné que l'inflammation aigüe suite à l'activation du facteur nucléaire kappaB (NF-KB) joue un rôle important dans la lésion de reperfusion, nous avons fait l'hypothèse que les poumons obtenus par DCD pourraient être traités pendant une EVLP avec du pyrrolidine dithiocarbamate (PDTC), un inhibiteur de NF-KB. Des poumons de rats exposés à 1 heure d'ischémie chaude suivie de 2 heures d'ischémie froide ont été placé dans un circuit EVLP pendant 4 heures, sans (groupe contrôle, N=6) ou avec l'addition de PDTC (2.Sg/1, groupe PDTC, n=6). La compliance pulmonaire statique (SPC), le pic de pression dans les voies aériennes (PAWP), les résistances vasculaires pulmonaires (PVR), et la capacité d'oxygénation ont été mesurées durant l'EVLP. Après l'EVLP, nous avons mesuré le gain de poids du bloc cœur-poumon (quantification de l'œdème), et la concentration de LDH (marqueur de lésion cellulaire), de protéine (marqueur d'œdème par perméabilité vasculaire augmentée) et des cytokines IL-6, TNF-a et CINC-1 dans le liquide de lavage broncho-alvéolaire (BAL), et nous avons évalué l'activation de NF-KB par le degré de phosphorylation et de dégradation de son inhibiteur IKBa dans le tissu pulmonaire. Dans le groupe contrôle, nous avons trouvé une activation significative de NF-KB, un œdème pulmonaire et une libération massive de LDH, protéines et cytokines. La SPC était significativement abaissée et le PAWP et les PVR augmentées, tandis que la capacité d'oxygénation tendait à baisser. Le traitement par PDTC durant l'EVLP a inhibé l'activation de NF-KB, n'a pas influencé la libération de LDH mais a diminué de façon marquée l'œdème pulmonaire et la concentration en protéine dans le BAL, a significativement diminué la libération de TNFa et IL-6, et a abrogé les changements de SPC, PAWP et PVR, avec une capacité d'oxygénation inchangée. En conclusion, l'inhibition de l'activation de la réponse immune innée durant l'EVLP en utilisant le PDTC comme inhibiteur de NF-KB a favorisé des améliorations significatives sur des poumons de rats endommagés suite à une ischémie chaude (poumons DCD). Des études futures devront déterminer si une telle stratégie de réhabilitation de greffon est adaptée pour la transplantation in-vivo. -- Damaged lung grafts obtained after circulatory death (DCD lungs) and warm ischemia may be at high risk of reperfusion injury after transplantation. Such lungs could be pharmacologically reconditioned using ex-vivo lung perfusion (EVLP). Since acute inflammation related to the activation of nuclear factor kappaB (NF-KB) is instrumental in lung reperfusion injury, we hypothesized that DCD lungs might be treated during EVLP by pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-KB. Rat lungs exposed to 1 h warm ischemia and 2 h cold ischemia were subjected to EVLP during 4h, in absence (CTRL group, N = 6) or in presence of PDTC (2.5g/L, PDTC group, N = 6). Static pulmonary compliance (SPC), peak airway pressure (PAWP), pulmonary vascular resistance (PVR), and oxygenation capacity were determined during EVLP. After EVLP, we measured the weight gain of the heart-lung block (edema), and the concentration of LDH (cell damage), proteins (permeability edema) and of the cytokines IL-6, TNF-a and CINC-1 in bronchoalveolar lavage (BAL), and we evaluated NF-KB activation by the degree of phosphorylation and degradation of its inhibitor I KBa in lung tissue. ln CTRL, we found significant NF-KB activation, lung edema, and a massive release of LDH, proteins and cytokines. SPC significantly decreased, PAWP and PVR increased, while oxygenation tended to decrease. Treatment with PDTC during EVLP inhibited NF-KB activation, did not influence LDH release, but markedly reduced lung edema and protein concentration in BAL, suppressed TNFa and IL-6 release, and abrogated the changes in SPC, PAWP and PVR, with unchanged oxygenation. ln conclusion, suppression of innate immune activation during EVLP using the NF-KB inhibitor PDTC promotes significant improvement of damaged rat DCD lungs. Future studies will determine if such rehabilitated lungs are suitable for in vivo transplantation

Clustering of HCV coinfections on HIV phylogeny indicates domestic and sexual transmission of HCV

Background: HCV coinfection remains a major cause of morbidity and mortality among HIV-infected individuals and its incidence has increased dramatically in HIV-infected men who have sex with men(MSM). Methods: Hepatitis C virus (HCV) coinfection in the Swiss HIV Cohort Study(SHCS) was studied by combining clinical data with HIV-1 pol-sequences from the SHCS Drug Resistance Database(DRDB). We inferred maximum-likelihood phylogenetic trees, determined Swiss HIV-transmission pairs as monophyletic patient pairs, and then considered the distribution of HCV on those pairs. Results: Among the 9748 patients in the SHCS-DRDB with known HCV status, 2768(28%) were HCV-positive. Focusing on subtype B(7644 patients), we identified 1555 potential HIV-1 transmission pairs. There, we found that, even after controlling for transmission group, calendar year, age and sex, the odds for an HCV coinfection were increased by an odds ratio (OR) of 3.2 [95% confidence interval (CI) 2.2, 4.7) if a patient clustered with another HCV-positive case. This strong association persisted if transmission groups of intravenous drug users (IDUs), MSMs and heterosexuals (HETs) were considered separately(in all cases OR >2). Finally we found that HCV incidence was increased by a hazard ratio of 2.1 (1.1, 3.8) for individuals paired with an HCV-positive partner. Conclusions: Patients whose HIV virus is closely related to the HIV virus of HIV/HCV-coinfected patients have a higher risk for carrying or acquiring HCV themselves. This indicates the occurrence of domestic and sexual HCV transmission and allows the identification of patients with a high HCV-infection ris

Pyrrolidine dithiocarbamate administered during ex-vivo lung perfusion promotes rehabilitation of injured donor rat lungs obtained after prolonged warm ischemia.

Damaged lung grafts obtained after circulatory death (DCD lungs) and warm ischemia may be at high risk of reperfusion injury after transplantation. Such lungs could be pharmacologically reconditioned using ex-vivo lung perfusion (EVLP). Since acute inflammation related to the activation of nuclear factor kappaB (NF-κB) is instrumental in lung reperfusion injury, we hypothesized that DCD lungs might be treated during EVLP by pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-κB. Rat lungs exposed to 1h warm ischemia and 2 h cold ischemia were subjected to EVLP during 4h, in absence (CTRL group, N = 6) or in presence of PDTC (2.5g/L, PDTC group, N = 6). Static pulmonary compliance (SPC), peak airway pressure (PAWP), pulmonary vascular resistance (PVR), and oxygenation capacity were determined during EVLP. After EVLP, we measured the weight gain of the heart-lung block (edema), and the concentration of LDH (cell damage), proteins (permeability edema) and of the cytokines IL-6, TNF-α and CINC-1 in bronchoalveolar lavage (BAL), and we evaluated NF-κB activation by the degree of phosphorylation and degradation of its inhibitor IκBα in lung tissue. In CTRL, we found significant NF-κB activation, lung edema, and a massive release of LDH, proteins and cytokines. SPC significantly decreased, PAWP and PVR increased, while oxygenation tended to decrease. Treatment with PDTC during EVLP inhibited NF-κB activation, did not influence LDH release, but markedly reduced lung edema and protein concentration in BAL, suppressed TNFα and IL-6 release, and abrogated the changes in SPC, PAWP and PVR, with unchanged oxygenation. In conclusion, suppression of innate immune activation during EVLP using the NF-κB inhibitor PDTC promotes significant improvement of damaged rat DCD lungs. Future studies will determine if such rehabilitated lungs are suitable for in vivo transplantation

High specificity of line-immunoassay based algorithms for recent HIV-1 infection independent of viral subtype and stage of disease

ABSTRACT: BACKGROUND: Serologic testing algorithms for recent HIV seroconversion (STARHS) provide important information for HIV surveillance. We have shown that a patient's antibody reaction in a confirmatory line immunoassay (INNO-LIATM HIV I/II Score, Innogenetics) provides information on the duration of infection. Here, we sought to further investigate the diagnostic specificity of various Inno-Lia algorithms and to identify factors affecting it. METHODS: Plasma samples of 714 selected patients of the Swiss HIV Cohort Study infected for longer than 12 months and representing all viral clades and stages of chronic HIV-1 infection were tested blindly by Inno-Lia and classified as either incident (up to 12 m) or older infection by 24 different algorithms. Of the total, 524 patients received HAART, 308 had HIV-1 RNA below 50 copies/mL, and 620 were infected by a HIV-1 non-B clade. Using logistic regression analysis we evaluated factors that might affect the specificity of these algorithms. RESULTS: HIV-1 RNA <50 copies/mL was associated with significantly lower reactivity to all five HIV-1 antigens of the Inno-Lia and impaired specificity of most algorithms. Among 412 patients either untreated or with HIV-1 RNA ≥50 copies/mL despite HAART, the median specificity of the algorithms was 96.5% (range 92.0-100%). The only factor that significantly promoted false-incident results in this group was age, with false-incident results increasing by a few percent per additional year. HIV-1 clade, HIV-1 RNA, CD4 percentage, sex, disease stage, and testing modalities exhibited no significance. Results were similar among 190 untreated patients. CONCLUSIONS: The specificity of most Inno-Lia algorithms was high and not affected by HIV-1 variability, advanced disease and other factors promoting false-recent results in other STARHS. Specificity should be good in any group of untreated HIV-1 patients

Higher Risk of Incident Hepatitis C Virus Coinfection Among Men Who Have Sex With Men, in Whom the HIV Genetic Bottleneck at Transmission Was Wide

Background. High-risk sexual behaviors have been suggested as drivers of the recent dramatic increase of sexually transmitted hepatitis C virus (HCV) among human immunodeficiency virus (HIV)-infected men who have sex with men (MSM). Methods. We assessed the association between the genetic bottleneck of HIV at transmission and the prevalence and incidence of HCV coinfection in HIV-infected MSM from the Swiss HIV Cohort Study (SHCS). As a proxy for the width of the transmission bottleneck, we used the fraction of ambiguous nucleotides detected by genotypic resistance tests sampled during early HIV infection. We defined a broad bottleneck as a fraction of ambiguous nucleotides exceeding a previously established threshold (0.5%). Results. From the SHCS, we identified 671 MSM with available results of HCV serologic tests and with an HIV genotypic resistance test performed during early HIV infection. Of those, 161 (24.0%) exhibited a broad HIV transmission bottleneck, 38 (5.7%) had at least 1 positive HCV test result, and 26 (3.9%) had an incident HCV infection. Individuals with broad HIV transmission bottlenecks exhibited a 2-fold higher odds of having ever experienced an HCV coinfection (odds ratio, 2.2 [95% confidence interval {CI}, 1.1-4.3]) and a 3-fold higher hazard of having an incident HCV infection (hazard ratio, 3.0 [95% CI, 1.4-6.6]) than individuals with narrow HIV transmission bottlenecks. Conclusions. Our results indicate that the currently occurring sexual spread of HCV is focused on MSM who are prone to exhibit broad HIV transmission bottlenecks. This is consistent with an important role of high-risk behavior and mucosal barrier impairment in the transmission of HCV among MS

Bilateral post-traumatic temporo-mandibular joint ankylosis in a 3-year-old child: a rare clinical case with a follow-up until completion of growth

Temporomandibular joint (TMJ) ankylosis is a severe condition which has a major impact on oral functions and, when affecting children, facial growth. The treatment is surgical and various techniques have been described. Few data are available concerning long-term growth following such treatment in paediatric cases. We present the case of a bilateral TMJ ankylosis following trauma in a 3-year-old child treated with interpositionnal arthroplasty using full-thickness skin graft. The patient was treated rapidly after diagnosis and was followed regularly until completion of growth. A sustained good maximal interincisal opening was obtained along with a satisfying mandibular growth. No complication was recorded, and no additional surgery needed. Excellent clinical results were obtained with a rather minor surgical treatment. The surgical technique used allowed a harmonious facial growth. TMJ ankylosis in children can be managed with good long-term functional and growth results when diagnosed and treated at an early stage.</p

Experimental ex vivo lung perfusion with sevoflurane: effects on damaged donor lung grafts

Abstract OBJECTIVES Volatile anaesthetics can provide significant protection against reperfusion injury in various experimental settings. The aim of this study was to assess the potential of sevoflurane treatment, the most commonly used volatile anaesthetic in modern anaesthesia, in rat lungs donated after circulatory death and reconditioned in an ex vivo lung perfusion (EVLP) system. METHODS Fifteen rats were sacrificed and divided into 3 groups. In the control and sevoflurane groups, the heart-lung blocks were exposed to 1 h of warm ischaemia and 2 h of cold ischaemia and were mounted on an EVLP circuit for 3 h, in the absence or in the presence of 2% sevoflurane. In the baseline group, heart-lung blocks were harvested immediately after euthanasia. Physiological data, lung nitro-oxidative stress, lactate dehydrogenase (LDH), expression of cytokines, oedema and histopathological findings were assessed during or post-EVLP. RESULTS The sevoflurane group showed significantly reduced LDH (8.82 ± 3.58 arbitrary unit vs 3.80 ± 3.02 arbitrary unit, P = 0.03), protein carbonyl (1.17 ± 0.44 nmol⋅mg−1 vs 0.55 ± 0.11 nmol⋅mg−1, P = 0.006), 3-nitrotyrosine (197.44 ± 18.47 pg⋅mg−1 vs 151.05 ± 23.54 pg⋅mg−1, P = 0.004), cytokine-induced neutrophil chemoattractant factor 1 (1.17 ± 0.32 ng⋅mg−1 vs 0.66 ± 0.28 ng⋅mg−1, P = 0.03) and tumour necrosis factor alpha (1.50 ± 0.59 vs 0.59 ± 0.38 ng⋅mg−1, P = 0.02) when compared with the control group. In addition, sevoflurane lungs gained significantly less weight (0.72 ± 0.09 g vs 0.72 ± 0.09 g, P = 0.044), had less perivascular oedema (0.58 ± 0.09 vs 0.47 ± 0.07, P = 0.036), and improved static pulmonary compliance (+0.215 ml⋅cmH2O−1, P = 0.003) and peak airways pressure (-1.33 cmH2O, P = 0.04) but similar oxygenation capacity (+1.61 mmHg, P = 0.77) and pulmonary vascular resistances (+0.078 mmHg⋅min⋅ml−1, P = 0.15) when compared with the control group. CONCLUSIONS These findings suggest that the potential of sevoflurane in protecting the lungs donated after cardiac death and reconditioned using EVLP could improve the outcome of these lungs following subsequent transplantation